I should clarify. I know where the teammate died, but after that they generally wont tell us what they saw while randomly pushing. Information like "3 at A" or "1 pushing long" goes a long way in winning the round.
I hate when people don't understand this, it bugs me so much.
Like, yes, there is a map. Sure, if I have my eyes glued to it, then I might see a few of the dots that pop up for a second before they '?' and fade, but I can't watch it all the time and it's so much easier to have a teammate make callouts so I can listen and still focus on what I'm doing. Even typed callouts are better than none because of longevity. Not to mention the dots only update when an ally sees the enemy, IIRC, so if an ally sees which direction said enemy is moving, they should call it out because the dots won' let you know that the enemy is moving to cat or wherever in some cases.
I don't know if any of this makes sense, I just woke up.